CPT International 02/2016

Figure 2: Final gating design: Temperature distribution at the end of filling. Right: Photo of the ejected casting
The first simulation results indicated
frame distortion values of up to 9 mm
lengthways and 5 mm crossways for the
initial gating design – results far from
the customer specification. The situation
was so severe that a complete redesign
of the gating system was the only
proper answer possible for the DGSteam.
The experts checked further experience-based
alternatives, again using
Magmasoft. According to DGS,
MAGMA 5 was a key factor to comply
with the timeline and secure the success
of the production process at the same
time (Figure 2).
The solution was eventually successfully
identified: a system with gating
are as in all four corners and a total of
20 ingates (Figure 3). Axel Schmidt recapitulates:
“To develop the design with
minimized frame distortion, MAGMA 5
played a crucial role. The possibility to
quickly and early test different variations
was essential, allowing us to create
the gating system in a way that it exercises
as little force on the casting as possible.
This way we could actually completely
avoid any critical distortion and
minimize other casting related defects
at the same time. The ‘material trace’ results
allowed us to check the symmetric
flow of the melt. And of course, the ‘distortion‘
result was used to analyze the
warping of the part in great detail and
document and discuss the effects of every
design modification”.
Next, the fixed casting lay-out had
to be transferred to the conditions of
the production environment. The design
and placement of the die inserts
and the cooling lines were the pending
major tasks. Again, the DGS team
used MAGMA 5 to develop the cooling
of the 10-fold divided die halves. Two
die halves weighing 14.1 and 20.3 t, optimized
with regard to the especially demanding
casting dimensions and cooling
requirements, were the final result.
The die was cleared for manufacturing
and the production could eventually
launch on time. Today, the final product
is an integral part of two different solar
collectors of leading manufacturers.
DGS strikes a positive balance.
Schmidt: “By using MAGMA 5 we succeeded
in producing the frame right
from the start, in accordance to the
strict demands regarding time and cost.
No in-production changes were necessary.
Today, in spite of the 24 kg shot
weight at only 6.3 kg component weight
and a form filling time of just 40 ms, the
frames are produced without critical distortion.
The project is not only an economic
success but also a recent proof of
the innovation ability of DGS.”
Meanwhile numerous new demanding
die castings are being developed at
Figure 3: Die cast part after removal
from the die casting cell
DGS. The DGS team is exploring the
new possibilities for virtual experimentation
and automatic optimization
in MAGMA 5 Rel. 5.3. The identification
of robust process conditions
and the active support in the assessment
of designs of experiments complement
their experience based efforts
well. DGS will continue to use
MAGMA 5 to open up further time and
cost potentials.
www.dgs-druckguss.com/en
www.magmasoft.de/en
DGS Druckguss Systeme AG is a globally active developer and producer of demanding
light alloy aluminum and magnesium die cast components, counting more
than 900 employees at its facilities in St. Gallen (Switzerland), Liberec (Czech Republic)
and Nansha (China). Since its foundation in 1950, the company has established
itself through its technology and production competence and uncompromising reliability
as an authoritative system supplier in the value chain of its customers, mainly
the automobile industry. DGS is ISO TS 16949, ISO 14001 und OHSAS 18001 certified.
Besides its production competence, DGS is an important development partner
for its customers, with a special focus on material and process development.
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